The patent PL 142779 discloses a device for the constant measurement of the oxygen amount in hot gases, based on a method of the use of heat of catalytic reaction of oxygen with hydrogen, while from the U.S. Pat. No. 3,849,539 a method is known for marking and deoxygenation from an inert gas stream with regard to hydrogen.
The method of measurement in accordance with the U.S. Pat. No. 3,849,539 cannot be used to determine the oxygen level directly in hot gases in view of the necessity of the initial and exact dry of the analyzed gas. Furthermore, the concentration of oxygen in the analysed gas must be less than 1% of the gravimetrical.
Emission and use of fuel control systems, consisting of three-way catalytic converters (TWC) using potentiometric oxygen sensors based on zirconium dioxide as well as amperometric sensors with linear lambda control based on zirconium dioxide (λ=1) are also known [E. Ivers-Tiffee, K. H. Hardtl, W. Menesklou, J. Riegel, Principles of solid state oxygen sensors for lean combustion gas control, Electrochimica Acta 47 (2001) 807-814]. The principle of operation of the above-mentioned sensors is connected with the electric current conduction, what is disadvantageous to certain solutions.
Solutions most closely related to the subject of the invention have been disclosed in U.S. Pat. No. 6,815,211 and publication US 2001031224 A1. In those solutions the devices made of systems, which on the basis of the signal from the quenching of luminescence provide information about the oxygen concentration in analysed gases, are described. The elements of those systems include:
(a) a device delivering measured gases, sensor sample chamber, in which the luminescence is being excited, and the fading time of which reflects the concentration of oxygen in gases; (b) a converter equipped with the source of light for the stimulation of the compound capable of luminescence in the sensor and sensitive light detector for the processing of emitted energy from the luminescent compound during the luminescence decay, which is being processed in the electric signal indicating the oxygen concentration in monitored gases, and (c) subsystems for the keeping of constant temperature of the sensor and processing of signal generated by the sensitive light detector. The disadvantage of the above-described solutions is complex structure.
The method of monitoring the oxygen concentration disclosed in U.S. Pat. No. 6,815,211, consists of the following stages: (a) formation of the solution composition showing luminescence in the organic solvent; (b) swelling of the matrix consisting of the hydrophobic polymer film containing large amount of the open micropores, (c) introduction of the solution composition showing luminescence to the film by its penetration inside the swollen film; (d) removal of the organic solvent in such a way, so that during the shrinkage, the microporous, hydrophobic polymer will trap at least half of the composition showing luminescence.
In the Paragraph 20 of U.S. Pat. No. 0,031,224, has been described an oxygen sensor from the zirconium oxide, in which the amount of oxygen is determined by the use of the ionic conductance. The solution similar to the subject of the invention is being also represented by the optical, fluorescent oxygen detector named “Rugged D.O.” (http://www.in-situ.com/In-Situ/Products/MPTROLL9000/TROLL9000_RDO.html), which enables the detection of oxygen concentration dissolved in aqueous solutions. The monitoring method is based on the fact, that the sensitive element of the detector (luminophore) is being activated and stimulated by the source of the blue light (e.g. UV LED). The detector element, which is being stimulated in this way, emits a red light of the intensity inversely proportional to the current oxygen concentration in water. Also the time length of the decay between the maximal blue light value and the maximal value of the response of the fluorescent red light is inversely proportional to the concentration of the present oxygen. The time of the decay can be expressed as a phase displacement between the incident blue light and the fluorescent red light.